Number of summer days

It is interesting to know that the average length of the northern hemisphere summer, calculated as the average time from the June solstice until the September equinox, is about 93 days and 15½ hours. On the contrary, the average length of the southern hemisphere summer, calculated as the average time from the December solstice until the March equinox, is about 89 days. Not too many people know that the southern hemisphere summers are shorter than the northern hemisphere summers because orbiting objects travel faster the closer they are to what they are orbiting. Moreover, Earth is closest to the sun in early January and farthest from the sun in early July.